function FindTree() -- Forgot parenthesis
  turtle.select(1)
  if turtle.compare() == true then
        return true
  else
        return false
  end
end

function cut() -- Forgot parenthesis
  while turtle.detectUp() do
    turtle.digUp()
    turtle.up()
  end
  while not turtle.detectDown() do
    turtle.down()
  end -- Forgot end
end

function plant()
  turtle.select(16)
  turtle.place()
end

function fuel()
  if turtle.getFuelLevel <10 then
    turtle.select(15)
    turtle.refuel(1)
  end -- Forgot end
end

fuel()
plant()
fuel()
if findTree() == false then
  cut()
else
  print ("error")
end -- Forgot end